When it comes to building little bridges over trenches a culvert is usually used so as not to impede the flow of water, whether the flow is permanent or occasional, as per after a rainfall. Culverts re made of various materials. The Most Popular are made of galvanized steel, plastics, and concrete. In centuries past, and still to this day, pieces of lumber were used to create culverts. They are usually fashioned in a way that is similar to the way barrels are made. What is difficult to achieve is the proper cutting angle which will give proper diameter. Also the angle from one piece of lumber must match the angle from the other piece of lumber connected to it.
There does not exist a device that can easily cut the pieces of lumber. There is therefore a need to for a faster, more convenient, and foolproof way of cutting pieces of lumber to the proper angle so as to obtain the proper sized cylindrical shape.